On the go and no time to finish that story right now? Your News is the place for you to save content to read later from any device. Register with us and content you save will appear here so you can access them to read later.

That compares with a previous record of 10.98 million trips in the 12 months to April 2012 - a period which included the boom time of the Rugby World Cup - before patronage slipped back below 10 million early last year.

Monthly bus travel was also up for February, by 7 per cent to 4.6 million trips, although 0.5 per cent fewer cyclists were counted at nine automatically monitored sites around Auckland.

The decline in ferry trips caused puzzlement and concern at an Auckland Transport board meeting, raising a promise by chief operating officer Greg Edmonds to investigate the cause and report back next month.

Mr Edmonds said the result appeared to be an anomaly, particularly in view of a strong season for cruise ship visits.

Board member Mike Lee, who is Auckland Council's infrastructure committee chairman, said it was particularly alarming after a 10 per cent fall in ferry patronage in January.

Although Waiheke ferries are run as commercial services without subsidies from Auckland Transport, Mr Lee said wharf taxes collected from them declined to $1.172 million last year, from $1.56 million in 2010.

"Something's not quite right and it needs to be investigated," he said.

Fullers ferry company operations general manager Tim Palmer said it had expected some fall in patronage, because of fewer events on Waiheke Island this summer, but that didn't account for the full shortfall.

He said the company would work with Auckland Transport to find the cause. In contrast, Auckland Transport chairman Lester Levy is hailing the new record for rail which has emerged since the board meeting, and has been reached just weeks before the first batch of new electric trains is due to start running on April 28 between Onehunga and Britomart.

"We are now seeing 5000 additional passenger journeys each business day compared to a year ago," he said. "People are responding to initial improvements such as integrated ticketing [through the AT Hop card], better on-time performance and improved facilities like the new transport hub at Panmure - and there's a lot more to come."